The objective of this case controlled study in head and neck cancer is to determine if phenotypic measures of drug metabolizing activity as measured by the Pittsburgh drug cocktail in the whole body or from quantitation of mRNA from individual drug metabolizing enzymes in oral cavity mucosa or tumor will be related to the risk of developing head and neck cancer. Measures of drug metabolizing activity will also be related to specific mutation of oncogene amplification as well as the biological behavior of the tumor.